Two sources tell The Canadian Press that Marc Nadon has an office at the Supreme Court building in Ottawa, even as his new office neighbours are preparing to judge his case.
A third source says the controversy is creating discomfort within the country's top legal institution.
In January, the eight current justices will consider whether Nadon is eligible to occupy the now-vacant ninth spot on the bench. The court had been asked to offer its opinion by the Conservative government, amid an ongoing controversy.
The appointment also faces a legal challenge from a Toronto lawyer who argues that the Ottawa-dwelling Federal Court judge does not meet the residency requirements, and the Quebec government has also contested the appointment.
Because Nadon has spent the last two decades on various federal courts, critics argue that he won't be familiar enough with Quebec's civil code to serve as one of the province's three guaranteed representatives on the high court.
The challenge, which is unusual in the naming of a Canadian Supreme Court justice, has already sidelined Nadon from hearing cases and left the high court short one judge.
Opposition parties are questioning the use of office space.
"Not only is this delicate for the Supreme Court judges, having to determine if their future colleague ... is qualified or not. If on top of that they're bumping into him (at work) and getting to know him better and better ... it doesn't seem too credible, this whole process," said the Bloc Quebecois' Andre Bellavance.
The NDP's Francoise Boivin said she believes the would-be nominee has settled into his space because he already has the prime minister's approval.
The Harper government argues that a Federal Court judge is perfectly qualified to serve and has tucked an amendment of the Supreme Court Act into a budget-implementation bill in support of its position.
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